Gage for cutting-bits.



' T. H. CLARKE.

I GAGE FOR CUTTING 511s.

APPUCATN FILED SEPT. 4,1914."

- ,Patented filly 4,1916.

- l {Mmi i M UNITED sTATEs PATENT oFFIcE,

THOMAS HUNT CLARKE, 0F CAMDEN, NEW JERSEY.

GAGE FOR CUTTING-BITS.

To all lwhom t may concern:

Be it known that I, THOMAS H. CLARKE, a citizen of the United States, residing at Camden, in the county of Camden and State of New Jersey, have indented new anduseful Improvements in Gages for Cutting- Bits, of whichl the following is a specification.

This invention relates to improvements in gages for cutting bits and has particular application to an adjustable bit carried gage.

In carrying out the present invention, it is my purpose to provide a' gage for cutting bits whereby the depth that the bit enters the hole being drilled maybe regulated soV that the cutting' end of the bit will penetrate the material to a predetermined degree. only.

It is also my purpose to provide a gage which will be found especially useful with cutting bits for drilling screw holes'whereby the depth of the hole will be regulated in accordance with the length of the screw.

Furthermore, I aim to provide a gage of the class described whereby the outer end wall of the hole will he countersunk to receive the head of the screw sa that the outer face` of such head will lie flush with the wood, metal or other material in which the hole is drilled.

-With the above and other objects in view, the invention consists 1n the constructiom combination and arrangement of parts hereinafter set forth in and falling Within the scope of the claims.

In the accompanying drawing, Figure 1 is a view in side elevation of *a drill bit land brace therefor, the bit being equipped with a gage constructed in accordance with the present invention. Fig. 2 is a view in side elevation of the gage showing the same applied to the bit. 3 is a vertical sectional view through the gage and adjacent portion of the bit. Fig. 4'is a cross sectional view on the line H of Fig. 3. Fig.' 5 is a perspective view of one part of the gage. Fig. 6 is a like view of the companion part. Fig. 7 is a similar -view of the cutting bit removed from the brace.

Referring now to the drawing in detail,

designates a breast braeehaving one end thereof equipped with the usual chuck 2, while 3 indicates a drill bit. In the present instance, the bit 3 comprises a main body portion 4 havingone end portion thereof square in cross section and tapering toward the outer end thereofas at 4 and provided,

Specication 4of Letters Patent.

Application 1ed September 4, 1914. Serial No. 860,239.

Patented July 4, 1916.

at the corners,`with cutting teeth 5, while the extremity is formed with the usual cutting threads 6 adapted to enter the material in advance of the teeth 5 so that the lastmentioned teeth may form threads in the wall of the openingbeing drilled. The chuck end of the body portion 4 is reduced to provide 'a shank T'designed to enter the chuck of the brace, while formedl in one side wall of the main body portion 4 of the bit adjacent to the chuck end thereof is a longitudinal groove 8 and disposed below the groove 48 and spaced apart vertically are notches 9. The opposite `side of the main body portion of the bit behind the groove 8 and series of notches 9 is formed with two series of notches 10` 10 respectively.

'In the present instance, my improved gage comprises a collar 11 surrounding the main body portion ofthe bit adjacent to the chuck end thereof and substantially square in cross section. Formed integral' with one edge of oneside of the collar 11 and' projecting toward the cutting end of the,bit parallel with the main body portion thereof is a plate 12 having the lower end thereof Jrormedvvith outwardly extending legs 13,13 contiguousvto the longitudinal edges of the plate vand spaced apart in parallelism, while formed in the plate 12 approximately centrally thereof adjacent to the last-mentioned end vthereofv is an opening-'14. Surrounding the main body portion of the cutting bit is a second collar 15 substantially square in cross section and 'spaced apart from the collar 11 and formed integral with one edge of one side of the co-llar 15 and projecting toward the Achuck end of the bit is a plate 16 overlying the plate 12 and in face to face contact therewith, while formed on the chuck end of the plate 16 contiguous to the longitudinal edges of such plate are legs 17, 17 spaced apart in parallelism and fitting within grooves 18,18 respectively formed in' the adjacent side of the sleeve 11, the legs 13 on the plate 12 fitting within grooves 19,19 respectively formed in the inner surface `of the adjacent side of the collar 15. 'Formed poSd within the collar l1 and enrling the f l adjacent portion of the bit is a bushing 25 oi a cross sectional configuration corresponding to 'that of the bore in the collar and the bit and "formed in opposite walls of the co und bushing 7% are alining o s hi'ch. are threaded set screws al,

thereof engaging the notches l and groove 8 respectively whereby the collar ll `Will'be held against longitudinal movement along the bit. vWhen thernut is tightened, the confronting faces of the plates and i6 are held in frictional engagement, thereby preventing relative longitudinal movement of such plates and collar ll.'

Surrounding the main body portion 4 of the bit is a sleeve Q''having one end thereof disposed within the collarl and the opposite end proj toward the cutting end of the bit. x .ed on the sleeve 25 approximately trally thereof is an outwardly pr' 7 flange 2S extending around the gud abutting the adjacent 1 l5, while disposed within outer surface of the sleeve a l? of cross sectional con- Y rresponding to that of the collar and threaded into alining ojienings inthe follar, bushing and sleeve are set scrcwsQS, haring the inner ends thereof capable of ,ngaging one of the notches iu the series 9 and l0 respectively so as to assure the holding of the gage against longitudinal movement on the bit. The outer edge of the sleeve is formed with' cutting teeth 2) spaced apart equal distances and lying against the adjacent portion of the'bit s0 as to engage thefouter end of the opening.

'drilled by the bit to countersink the same. In the present instance, the longitudinal side walls of the slot 2O are serrated as at 30 and the serrations upon one edge aline with those on the opposite edge to form, in effeet, openings apable of interchangeable registration with the opening 14.

in practice, the chuck end of the bit is secured within the chuck 2 in the usual well known ina-nner and the set screws Qi and 28 loosened so that the gage may be adjusted, as an entirety, longitudinally of the bit and locked in the desired adjusted position. Should it be desired to obtain a very line adjustment, the set screws 28 remain loose, while the set screws Q4 are tightened and the thumb nut is loosened so that the collar l5 carrying the sleeve may be adjusted 'upon the bit relatively to the collar 11, the outer edge of the sleeve being disposed a distance from the cutting end ofthe bit equalto the depth of the hole to be out or drilled. ils the bit penetrates the material to the required depth 'the teeth 29 countersink the Ween the inner surface lof outer end of the hole. ln the use of the bit 3, the cutting end 6 thereof penetrates the materiali, While the teeth 5 at the corners of the tapered cutting end portion of the bit act upon the wall of the opening to form screw threads therein so that a screw may be threaded into the opening formed by the cutting bit with ease and facility.

From the foregoing description taken in connection with the accompanying drawing, vthe construction, mode of operation and manner of employingl my improved gage will be readily apparent. lt Will be seen that l have provided a gage'jvvhereby the depth that the cutting bit enters the hole being drilled may be limited and whereby the outer end of such hole will be countersunk.

I claim:

LA gage for cutting bits comprising a collar adapted to surround the bit adjacent the brace end thereof, a plate depending from the inner surface of-one side of the collar, the outer surface of saidlr side having spaced vertical grooves, a second collar adapted' to surround the bit below the first collar and at a remote point therefrom, a plate rising from the outer surface of one side of theI second collar, the inner surface of said side having spaced vertical grooves,

said )lates bein" arran .ed in face to face' contact and Slidably adj'ustable relatively, means for holding said plates xed 'relatively, spaced parallellegs projecting from ,the free endiof each of said plates contiguous yto the longitudinal edges thereof, the .legs of one plate' being arranged in the said grooves in the collarcarried by the other plate, and means for holding the collars fixed upon said bit. Y

2. A gage for `cutting bits comprising a collar'ftidapted to'surround .the bit adjacent the brace end thereof, a plate depending from one 'side of the collar, a sleeve surrounding the bit adjacent the cutting end thereof, a laterally disposed flange formedon the upper end" of said sleeve, cutting 'teeth formed on the lower end thereof, a bushing rising from said flange in alinement with said sleeve and embracing said bit, a second. collar surrounding said bushing and resting upon said Harige, a plate extending upwardly -from .the `second mentioned collar lin face to face contact with the first mentioned plate, means for hold-- ing said-collars-ixed relatively, said plates being slidably adjustable, and means for holding 'said plates in fixed relation.A

ln testimony whereof I affix my signature in' presence of two witnesses.

THOM XS HUNT CLARKE. Witnesses:

Jas. A.. CLARKE, JAS. L. CLARKE. 

